Biology subjects

Harrison, O. K.

Publications and source records attributed to Harrison, O. K..

7 recordsLinked to original sources

bioRxiv2021

The Respiratory Resistance Sensitivity Task: An Automated Method for Quantifying Respiratory Interoception and Metacognition

The ability to sense, monitor, and control respiration - e.g., respiratory interoception (henceforth, respiroception) is a core homeostatic ability. Beyond the regulation of gas exchange, enhanced awareness of respiratory sensations is directly related to psychiatric symptoms such as panic and anxiety. Indeed, chronic breathlessness (dyspnea) is associated with a fourfold increase in the risk of developing depression and anxiety, and the regulation of the breath is a key aspect of many mindfulness-based approaches to the treatment of mental illness. Physiologically speaking, the ability to accurately monitor respiratory sensations is important for optimizing cardiorespiratory function during athletic exertion, and can be a key indicator of illness. Given the important role of respiroception in mental and physical health, it is unsurprising that there is increased interest in the quantification of respiratory psychophysiology across different perceptual and metacognitive levels of the psychological hierarchy. Compared to other more popular modalities of interoception, such as in the cardiac domain, there are relatively few methods available for measuring aspects of respiroception. Existing inspiratory loading tasks are difficult to administer and frequently require expensive medical equipment, or offer poor granularity in their quantification of respiratory-related perceptual ability. To facilitate the study of respiroception, we here present a new, fully automated and computer-controlled apparatus and psychophysiological method, which can flexibly and easily measure respiratory-related interoceptive sensitivity, bias and metacognition, in as little as 30 minutes of testing, using easy to make 3D printable parts.

neuroscience↗

bioRxiv2021

Baseline psychological traits contribute to Lake Louise Acute Mountain Sickness score at high altitude

BackgroundInteroception refers to an individuals ability to sense their internal bodily sensations. Acute mountain sickness (AMS) is a common feature of ascent to high altitude that is only partially explained by measures of peripheral physiology. We hypothesised that interoceptive ability may explain the disconnect between measures of physiology and symptom experience in AMS. Methods and MaterialTwo groups of 18 participants were recruited to complete a respiratory interoceptive task three times at two-week intervals. The control group remained in Birmingham (140m altitude) for all three tests. The altitude group completed test 1 in Birmingham, test 2 the day after arrival at 2624m, and test 3 at 2728m after an 11-day trek at high altitude (up to 4800m). ResultsBy measuring changes to metacognitive performance, we showed that acute ascent to altitude neither presented an interoceptive challenge, nor acted as interoceptive training. However, AMS symptom burden throughout the trek was found to relate to sea-level measures of anxiety, agoraphobia, and neuroticism. ConclusionsThis suggests that the Lake Louise AMS score is not solely a reflection of physiological changes on ascent to high altitude, despite often being used as such by researchers and commercial trekking companies alike.

neuroscience↗

bioRxiv2021

Interoception of breathing and its relationship with anxiety

Interoception, the perception of internal bodily states, is thought to be inextricably linked to affective qualities such as anxiety. While interoception spans sensory to metacognitive processing, it is not clear whether anxiety is differentially related to these processing levels. Here we investigated this question in the domain of breathing, using computational modelling and high-field (7 Tesla) fMRI to assess brain activity relating to dynamic changes in inspiratory resistance of varying predictability. Notably, the anterior insula was associated with both breathing-related prediction certainty and prediction errors, suggesting an important role in representing and updating models of the body. Individuals with low vs. moderate anxiety traits showed differential anterior insula activity for prediction certainty. Multimodal analyses of data from fMRI, computational assessments of breathing-related metacognition, and questionnaires demonstrated that anxiety-interoception links span all levels from perceptual sensitivity to metacognition, with strong effects seen at higher levels of interoceptive processes.

neuroscience↗

bioRxiv2021

TAPAS: an open-source software package for Translational Neuromodeling and Computational Psychiatry

Psychiatry faces fundamental challenges with regard to mechanistically guided differential diagnosis, as well as prediction of clinical trajectories and treatment response of individual patients. This has motivated the genesis of two closely intertwined fields: (i) Translational Neuromodeling (TN), which develops "computational assays" for inferring patient-specific disease processes from neuroimaging, electrophysiological, and behavioral data; and (ii) Computational Psychiatry (CP), with the goal of incorporating computational assays into clinical decision making in everyday practice. In order to serve as objective and reliable tools for clinical routine, computational assays require end-to-end pipelines from raw data (input) to clinically useful information (output). While these are yet to be established in clinical practice, individual components of this general end-to-end pipeline are being developed and made openly available for community use. In this paper, we present the Translational Algorithms for Psychiatry-Advancing Science (TAPAS) software package, an open-source collection of building blocks for computational assays in psychiatry. Collectively, the tools in TAPAS presently cover several important aspects of the desired end-to-end pipeline, including: (i) tailored experimental designs and optimization of measurement strategy prior to data acquisition, (ii) quality control during data acquisition, and (iii) artifact correction, statistical inference, and clinical application after data acquisition. Here, we review the different tools within TAPAS and illustrate how these may help provide a deeper understanding of neural and cognitive mechanisms of disease, with the ultimate goal of establishing automatized pipelines for predictions about individual patients. We hope that the openly available tools in TAPAS will contribute to the further development of TN/CP and facilitate the translation of advances in computational neuroscience into clinically relevant computational assays.

neuroscience↗

bioRxiv2020

Dissociating breathlessness symptoms from mood in asthma

Asthma is one of many chronic diseases in which discordance between objectively measured pathophysiology and symptom burden is well recognised. Understanding the influences on symptom burden beyond pathophysiology could improve our ability to treat symptoms. While co-morbidities such as anxiety and depression may play a role, the impact of this relationship with symptoms on our ability to perceive bodily sensations (termed interoception), or even our general and symptom-specific attention is not yet understood. Here we studied 63 individuals with asthma and 30 healthy controls. Alongside physiological tests including spirometry, bronchodilator responsiveness, expired nitric oxide and blood eosinophils, we collected self-reported questionnaires covering affective factors such as anxiety and depression, as well as asthma symptoms and asthma-related quality of life (individuals with asthma only). Participants additionally completed a breathing-related interoception task and two attention tasks designed to measure responsiveness to general temporal/spatial cues and specific asthma-related threatening words. We conducted an exploratory factor analysis across the questionnaires which gave rise to key components of Mood and Symptoms, and compared these to physiological, interoceptive and attention measures. While no relationships were found between symptoms and physiological measures in asthma alone, negative mood was related to both decreased interoceptive metacognitive sensitivity ( insight into interoceptive performance) and metacognitive bias (confidence in interoceptive decisions), as well as increased effects of spatial orienting cues in both asthma and controls. Furthermore, the relationship between the extent of symptoms and negative mood revealed potential sub-groups within asthma, with those who displayed the most severe symptoms without concurrent negative mood also demonstrating altered physiological, interoceptive and attention measures. Our findings are a step towards understanding how both symptoms and mood are related to our ability to interpret bodily symptoms, and to explore how the balance between mood and symptoms may help us understand the heterogeneity in conditions such as asthma.

neuroscience↗

bioRxiv2020

The Filter Detection Task for measurement of breathing-related interoception and metacognition

The study of the brains processing of sensory inputs from within the body ( interoception) has been gaining rapid popularity in neuroscience, where interoceptive disturbances are thought to exist across a wide range of chronic physiological and psychological conditions. Here we present a task and analysis procedure to quantify specific dimensions of breathing-related interoception, including interoceptive sensitivity (accuracy), decision bias, metacognitive bias, and metacognitive performance. Two major developments address some of the challenges presented by low trial numbers in interoceptive experiments: (i) a novel adaptive algorithm to maintain task performance at 70-75% accuracy; (ii) an extended hierarchical metacognitive model to estimate regression parameters linking metacognitive performance to relevant (e.g. clinical) variables. We demonstrate the utility of the task and analysis developments, using both simulated data and three empirical datasets. This methodology represents an important step towards accurately quantifying interoceptive dimensions from a simple experimental procedure that is compatible with clinical settings.

neuroscience↗

bioRxiv2020

Pain and breathlessness: Salient, somatosensory and similar, but not the same

Quantifying pain currently relies upon subjective self-report. Alongside the inherent variability embedded within these metrics, added complications include the influence of ambiguous or prolonged noxious inputs, or in situations when communication may be compromised. As such, there is continued interest in the development of brain biomarkers of pain, such as in the form of neural signatures of brain activity. However, issues pertaining to pain-related specificity remain, and by understanding the current limits of these signatures we can both progress their development and investigate the potentially generalizable properties of pain to other salient and/or somatomotor tasks. Here, we utilized two independent datasets to test one of the established Neural Pain Signatures (the NPS (Wager et al. 2013)). In Study 1, brain activity was measured using functional magnetic resonance imaging (fMRI) in 40 healthy subjects during experimentally induced breathlessness, conditioned anticipation of breathlessness and a simple finger opposition task. In Study 2, brain activity was again measured during anticipation and breathlessness in 19 healthy subjects, as well as a modulation with the opioid remifentanil. We were able to identify significant NPS-related brain activity during anticipation and perception of breathlessness, as well as during finger opposition using the global NPS. Furthermore, localised NPS responses were found in early somatomotor regions, bilateral insula and dorsal anterior cingulate for breathlessness and finger opposition. In contrast, no conditions were able to activate the local signature in the dorsal posterior insula - thought to be critical for pain perception. These results provide properties of the present boundaries of the NPS, and offer insight into the overlap between breathlessness and somatomotor conditions with pain.

neuroscience↗